Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA looks to solar eclipse to help understand Earth's energy system

21.07.2017

It was midafternoon, but it was dark in an area in Boulder, Colorado on Aug. 3, 1998. A thick cloud appeared overhead and dimmed the land below for more than 30 minutes. Well-calibrated radiometers showed that there were very low levels of light reaching the ground, sufficiently low that researchers decided to simulate this interesting event with computer models. Now in 2017, inspired by the event in Boulder, NASA scientists will explore the moon's eclipse of the sun to learn more about Earth's energy system.

On Aug. 21, 2017, scientists are looking to this year's total solar eclipse passing across America to improve our modelling capabilities of Earth's energy. Guoyong Wen, a NASA scientist working for Morgan State University in Baltimore, is leading a team to gather data from the ground and satellites before, during and after the eclipse so they can simulate this year's eclipse using an advanced computer model, called a 3-D radiative transfer model.


DSCOVR's Earth Polychromatic Imaging Camera (EPIC) will capture images similar to this one from the Lagrange 1 point, about a million miles away from Earth.

Credits: NASA/Katy Mersmann

If successful, Wen and his team will help develop new calculations that improve our estimates of the amount of solar energy reaching the ground, and our understanding of one of the key players in regulating Earth's energy system, clouds.

Earth's energy system is in a constant dance to maintain a balance between incoming radiation from the sun and outgoing radiation from Earth to space, which scientists call the Earth's energy budget. The role of clouds, both thick and thin, is important in their effect on energy balance.

Like a giant cloud, the moon during the 2017 total solar eclipse will cast a large shadow across a swath of the United States. Wen and his team already know the dimensions and light-blocking properties of the moon, but will use ground and space instruments to learn how this large shadow affects the amount of sunlight reaching Earth's surface, especially around the edges of the shadow.

"This is the first time we're able to use measurements from the ground and from space to simulate the moon's shadow going across the face of Earth in the United States and calculating energy reaching the Earth," said Wen. Scientists have made extensive atmospheric measurements during eclipses before, but this is the first opportunity to collect coordinated data from the ground and from a spacecraft that observes the entire sunlit Earth during an eclipse, thanks to the National Oceanic and Atmospheric Administration's Deep Space Climate Observatory launched (DSCOVR) in February 2015.

Even though the moon blocking the sun during a solar eclipse and clouds blocking sunlight to Earth's surface are two different phenomena, both require similar mathematical calculations to accurately understand their effects. Wen anticipates this experiment will help improve the current model calculations and our knowledge of clouds, specifically thicker, low altitude clouds that may cover about 30 percent of the planet at any given time.

In this experiment, Wen and his team will simulate the total solar eclipse in a 3-D radiative transfer model, which helps scientists understand how energy is propagated on Earth. Currently, models tend to depict clouds in one dimension. In many cases, these one dimensional calculations can create useful science models for understanding the atmosphere. Sometimes though, a three-dimensional calculation is needed to provide more accurate results. The big difference is that 3-D clouds reflect or scatter solar energy in many directions, from the top and bottom, and also out of the sides of clouds. This 3-D behavior results in different amounts of energy reaching the ground than a one-dimensional model could predict.

"We're testing the ability to do a certain kind of complex calculation, a test of a 3-D mathematical technique, to see if this is an improvement over the previous technique," said Jay Herman, scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and co-investigator of the project. "If this is successful, then we will have a better tool to implement in climate models and can use it to answer questions and the Earth's energy budget and climate." For the upcoming eclipse, Wen and his team members will be stationed in Casper, Wyoming, and Columbia, Missouri to gather information on the amount of energy being transmitted to and from Earth before, during and right after the eclipse with several ground instruments.

A ground-based, NASA-developed Pandora Spectrometer Instrument will provide information on how much of any given wavelength of light is present, and a pyranometer will measure total solar energy from all directions coming down toward the surface. Immediately before and after the eclipse scientists will measure other information such as the amount of absorbing trace gases in the atmosphere, such as ozone, nitrogen dioxide and small aerosol particles to also use in the 3-D model.

Meanwhile in space, NASA's Earth Polychromatic Imaging Camera, or EPIC, instrument aboard the DSCOVR spacecraft, will observe the light leaving Earth and allow scientists to estimate of the amount of light reaching the earth's surface. Additionally, NASA's two MODIS satellite instruments, aboard the agency's Terra and Aqua satellites, launched in 1999 and 2002, respectively, will provide observations of atmospheric and surface conditions at times before and after the eclipse. The scientists will then combine ground measurements with those observed by the spacecraft.

This experiment complements NASA's decades-long commitment to observing and understanding contributions to Earth's energy budget. For more than 30 years, NASA has measured and calculated the amount of solar energy hitting the top of our atmosphere, the amount of the sun's energy reflected back to space and how much thermal energy is emitted by our planet to space. These measurements have been possible thanks to instruments and missions such as ACRIMSAT and SOLSTICE (launched in 1991), and SORCE, launched in 2003 as well as the series of CERES instruments flown aboard Terra, Aqua, and Suomi-NPP (launched in 2011).

This fall, NASA will continue to monitor the sun-Earth relationship by launching the Total and Spectral Solar Irradiance Sensor-1, or TSIS-1, to the International Space Station and the sixth Clouds and the Earth's Radiant Energy System CERES instrument, CERES FM6, to orbit later this year. Five CERES instruments are currently on orbit aboard three satellites.

Rob Gutro | EurekAlert!

More articles from Earth Sciences:

nachricht Clear as mud: Desiccation cracks help reveal the shape of water on Mars
20.04.2018 | Geological Society of America

nachricht Hurricane Harvey: Dutch-Texan research shows most fatalities occurred outside flood zones
19.04.2018 | European Geosciences Union

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>